The disclosure relates generally to noise reduction and cooling a working fluid, such as the inlet air of a turbomachine. More specifically, the disclosure relates to assemblies with a fibrous medium which provide turbine noise reduction in addition to cooling.
Conventional turbine systems are frequently used to generate power for, e.g., electric generators. A working fluid, such as hot gas or steam can be forced across sets of turbine blades, which are coupled to a rotor of the turbine system. The force of the working fluid on the blades causes those blades (and the coupled body of the rotor) to rotate. In many cases, the rotor body is coupled to the drive shaft of a dynamoelectric machine such as an electric generator. In this sense, initiating rotation of the turbine system rotor can also rotate the drive shaft in the electric generator to generate an electrical current (associated with a power output).
Variables such as the turbine's efficiency, power output, and risk of failure are at least partially dependent on the internal temperature of particular components and passages, such as inlets, outlets, etc. The temperature of a working fluid flowing through the turbine system will affect outputs, such as the rotation torque and/or power generated. Designing a turbine system to have a particular operating temperature can improve these outputs. The process of controlling operating temperatures to increase the power output of a system can be known as “turbine power augmentation.” To manage the temperature of a turbine system, various cooling systems may be deployed.
Another set of variables which can affect the turbine's performance and safety, particularly in a gas turbine, are dynamic outputs (i.e., noise) produced by the turbine during operation. The amount of noise produced may be greater in a land based gas turbine than in other types of turbomachinery because of different operational characteristics, e.g., higher compressor rotor tip speed. Thus, some materials or components of a turbine may be designed or selected based on their ability to suppress acoustic waves.